Lightning arrester



Dec. 11, 1934. A T, CARTER 1,984,333

LIGHTNING ARRESTER Filed sept. 21, 1928 l Patented Dec. 1l, 1934 UNITEDSTATES PATENT OFFICE LIGHTNING ABBESTER Ainslie T. Carter, Coldwater, N.Y., assignor to General Railway Signal Company, Rochester,

Application September 21, 1928, Serial No. 307,471

7 Claims. (Cl. 175-30) This invention relates in general to lightning er9 of conducting material is likewise received arresters. and has moreparticular reference to on each of the studs 'I so as to bear fiatagainst an arrester of the vacuum tube type having an the correspondingwashers 8. Holding the air spark gap in multiple with the tube. washers8 and 9 in place against each other and In lightning arresters of thegas tube type, against the crimped over portion 51 of cylinder 5 thereis always the danger of the tube failing 5, are the sleeves 4 which areheld in place on and hence of losing proper protection. In orstuds 7 bymeans of solder or the like 41. der to avoid this danger, it is usual toprovide, in Within the cartridge C is a sealed glass tube multiple withthe gas tube, a usual spark gap 10, having lead-in wires ll sealed inthe ends 10 type of arrester having a break down voltage cf the tube 10and in the solder 41 and connect- 10 somewhat greater than the breakdown voltage ed within the tube 10 to spaced electrodes 12. of the gastube so that the gas tube normally The tube is filled with neon gas, orother usual functions to ground excessive currents but in or suitablegas, under subatmosphcric pressure, the event of its failure the airspark gap will in a manner usual in such devices. l5 afford properprotection. Diagrammatically shown at 13 is a relay con- 15 It is oneobject of this invention to provide a nected up as shown in Figs. l and3 so as to simple and economical means of providing an be energizedthrough a circuit including one air spark gap which will be uniform andprcdeterminal B of a source of energy, binding post termined in lengthin all arresters produced. 2 and adjacent post 21, the winding of relayFurther objects, purposes and characteristic 13, and the other terminalC of the source. Flow 2,0 features of the present invention will appearas from the terminal B of the source of energy, the descriptionprogresses. reference being had also can take place, if the voltage issufficiently to the accompanying drawing showing, solely high, through aparallel path to ground 14, this by way of example, and not in anymanner parallel path including, in parallel, one circuit whatsoever in alimiting sense, one form which including the gap between the electrodes12, and

the invention can assume. In the drawing:- a second circuit includingthe two air gaps be- Fig. 1 is a side elevation of one form of the tweenthe conducting washers 9 and the ends invention, with parts shown insection. 51 of cylinders 5, in series.

Fig. 2 is an axial sectional View through a The structure forming thetwo air gaps in lightning arrester cartridge constructed in acseriesbetween the washers 9, and the crimped 3U cordance with this invention.over ends 51 of cylinder 5, insures accurately Fig. 3 is a diagrammaticview of the invention. formed air gaps of invariable and predeterminedReferring now to the drawing, the lightning length so long as the washer8 be accurately arrester comprises an insulating base l ofpordimensioned. It is a very simple matter to form celain or the like,to which are connected bindthese washers 8 of predetermined and uniform3,-, ing posts 2 and 21. Connected to the base l by dimensions, andhence a simple and economical the binding posts 21, are receiving clips3 formed construction has been afforded which insures of electricallyconducting springy material uniform air gaps of predetermineddimensions.

spaced so as to readily receive an arrester car- It is most importantthat these air gaps be tridge C, by means of the projecting conductingformed accurately, and of the desired prede- 4U sleeves 4 on thecartridge. termined dimensions, since if they are too short Thecartridge C comprises a hollow cylindrithe break down Voltage across thetwo air gaps cal Conducting Shell 5, fOrmed preferably 0f in series maybe less than that across the elecmetal, with end discs 6 0f porcelain 0rother trades 12, with the result that air gaps and not non-conductingmaterial, over which the ends the gas tube, normally functions to carefor 45 0f the Cylinder 5 are crimped, aS ShOWIl at 51, overloads. On theother hand, if the two air the ends 51 0f Cylinder 5. v@Xtendng Onlypart gaps in series be too long, the break down voltage way across theouter face of each disc 6. A may be so great that even on failure of thegas conducting stud 7 passes through each disc 6 tube, no current willflow to ground upon excesand projects outwardly beyond the outer face ofsive voltage, and hence no secondary protection 50 its disc so as toreceive awasher 8 of non-conwill be afforded the translating device 13,upon ducting material, accurately formed in its varifailure of the tube10. ous dimensions so as to snugly fit over the stud The above ratherspecific description of one 7, and bearing flat against the crimped orbendform of the present invention, is given solely 55 ed over portion 51of cylinder 5. A second washby way of illustration, and is not intended,in 55 Having described my invention, I now claim:-

1. In a lightning arrester, an arrester unit, said unit comprising, ahollow open endedvshell of conducting material, an end piece ofinsulating material forming each end of said shell with said conductingmaterial crimped over the outer end of each end piece, a conductingstudspaced from said. crimped ends and. passingthrough each end piece andprojecting beyond ,the outer face of each end piece, an accuratelyformed insulating washer on each stud and'bearing at against saidcrimped overparts of said shell, and a conducting washeron each stud andbearing flat against said insulating Washer, Uwhereby to form aninvariable air gap of predetermined size between said conducting-shelland said conductinglwashers.

2. In a lightning arrester, in combination, an open ended cylindricalmetallic shell, a non- -conducting disc in each end lof said shell, aconducting st-ud projecting out from each disc, each end of said shellbeing crimped over the outer face'of each disc and out of contact withsaid studs, an accurately formed insulating washer on each stud andbearing flat against the crimped over parts of said shell, and a Washerof conducting material on each stud and bearing against each insulatingwasher.

3. In a lightning arrester, in combination, an open ended cylindricalmetallic shell, a nonconducting disc in each end of said shell, aconducting stud projecting out from each disc, each end of said shellbeing crimped over the outer face of each disc and out of contact withsaid studs, an accurately formed insulating washer on each stud andbearing flat against the crimped `,over parts of said shell, a washer ofconducting. material on each stud and bearing against each insulatingwasher, a sleeve passing cver each stud and bearing against said washersto hold them in contact with each other and said shell, and solderconnecting said sleevesrand studs. 4

4. In a lightningarrester, in combination an open ended cylindricalmeta`.lli c .shell,l av non-- conducting disc vin each'- end of saidShell, yaconducting stud'` projecting -out from ,."each disc,

each Aend of said. shell' being crimped over the outer face of each discvand out of Contact with '.said studs, an accurately -formed insulatingwasher o'fpredetermineddimensions on each stud andbearingat againstthecrimped over parts of said shell, a washer of conducting ma..

terial -on each stud and bearing against each Ainsulatinlr Washer, asleeve passing over each stud and bearing against said Washers to holdthemincontact With each other and with said shell, solder connectingsaid sleeves and studs, lead-in wires passing from said solder andthrough said studs and into said shell, and a rare gas tube lightningarrester within said shell and connected to said wires.

5. In a lightning arrester, in combination, an open ended metallicshell, a non-conducting head in each end of the shell, a conducting studprojecting out from each head, a Washer of conducting material en eachstud, and an insulating washer on each stud and electrically insulatingeach conducting Washer from the shell.

6. A lightning arrester of the cartridge type comprising a metal shell,and spark gap elements each consisting of a current conducting elementheld spaced from an end of the shell by a suitable insulator insertedtherebetween whereby the shell serves to interconnect the elementsthrough gaps determined by the insulators, in series relation.

7. A lightning arrester of the cartridge type including, a shell,insulators carried at each end of the shell, spark gap elements on eachof said insulators, each including an end of the shell, a conductingWasher, and an insulating Washer of a desired thickness separating theconducting washer from the end of the shell, said shell thus serving tointerconnect said spark gap elements on said insulators in series.

AINSLIE T. CARTER.

